EP0141391B1 - Continuous film strip copier and method of monitoring the synchrony of the film movement and the film data in a continnous film strip copier - Google Patents

Description

The invention relates to a method for monitoring the synchronism of the film run and the measurement data in a roll copier according to the preamble of claim 1 and a roll copier for performing this method.

A roll copier is known from German patent 19 14 360, in which the color density values of an entire film are measured and evaluated before the copying process for the first copy of this film is carried out. In this way, the measured values of the entire film are available, which enables a more precise determination of the amounts of copying light. A film memory is provided for recording the film between the measuring and copying station, and is dimensioned such that the longest of the individual films occurring during normal operation is accommodated in the memory. In order to be equipped for different film lengths, the storage capacity can be changed by a movable set of rollers.

This configuration of the film memory assumes that only films of a certain length are initially contained in a film roll to be processed. If this film length is changed, the film memory must be changed.

However, the practical copying operation requires that films of different lengths can optionally be combined into a film strip. In particular in the case of film assembly 135, films with 36 master copies, with 24 master copies and with 12 master copies of the 24 x 36 mm format can appear mixed. In unfavorable cases, sections of torn films with an even shorter length can also be contained in the roll. As a result, in the area between the scanning station and the copying station, i. H. the storage area, more than one glue point can be included. This creates problems, i. that is, there is a risk that a film strip in the copying station can be assigned measurement data which were measured in the measuring station on another film strip.

The object of the invention is to provide a method that correctly merges copy templates and measurement data, or copy values calculated therefrom, in the copying station, i. i.e., avoid misassignments with the greatest possible probability.

This object is achieved by the method according to claim 1 and in the case of a roll copier according to claim 5.

By creating a defined path length between the sensors for gluing points in the measuring station and in the copying station by transferring the film memory to the minimum filling position, the path of a gluing point from the measuring station to the copying station can be followed exactly by measuring the path length covered in the copying station a reliable statement can be made about the arrival of precisely this adhesive point in the copying station. This reliable statement is also possible if, for. B. by a large number of short pieces of film between the measuring and the copying station more than one glue point is present. This process can also be carried out if, for. B. in the course of repair work the film was moved back and forth in the copying station or other manipulations were carried out. According to an embodiment of the invention, this is also possible as a routine, random check.

• Fig. 1 ein Prinzipbild eines bekannten Kopiergerätes,
• Fig. 2 einen zum Kopieren vorgesehenen Filmstreifen mit Klebestelle und
• Fig. 3a bis 3e verschiedene Phasen eines Vorgangs zur Überwachung der Synchronität beim Transport des Films von der Meßstation zur Kopierstation.

Further details and advantages of the invention emerge from the subclaims in connection with the description of an exemplary embodiment which is explained in detail on the basis of figures of the known device with reference to the drawing. Show it:

• 1 is a schematic diagram of a known copier,
• Fig. 2 is a film strip intended for copying with glue and
• 3a to 3e different phases of a process for monitoring the synchronicity when transporting the film from the measuring station to the copying station.

In Fig. 1, a copier known from German patent 19 14 360 is shown, in which a film 1 assembled from many film strips to form a long tape from an unwinding roller 3 via deflection rollers 4, 5, 16, a memory 17 with deflection rollers 18 and others Deflection rollers 42, 43 is guided to a take-up reel 44. In a measuring station 6, the continuous film is measured for its density by means of photoelectric cells 9, 10 and 11 with corresponding color filters 12, 13, 14 due to the transillumination using a light source 7 in a housing and a condenser 8. The measured values are evaluated in an evaluation circuit 15 and forwarded to an exposure control device 41. In the copying station 19, a light source 21 with a reflector 22 and a condenser 23, a deflecting mirror 24 is arranged in front of a mixing shaft 25, which has a diffusing screen 26 on its exit side. Subtractive color filters 27, 28 and 29 of maximum density are located in front of the mixing shaft and can be pushed more or less far into the beam path by servomotors 30, 31 and 32. Behind the copying window, part of the copying light is thrown through a partially transparent mirror 33 onto a further measuring device 34, 35 which acts on the individual template and controls a shutter 36. The original is imaged in the copying window on a copying material band 38 by an objective 37, which is guided from an unwinding spool 39 to a winding spool 40.

According to FIG. 2, the film 1 to be copied has template fields 1a, which according to FIG. 2 be square, but can also have the long format 24 x 36 or the half format 18 x 24 mm. In each case the templates 1a are assigned position notches 1c, which serve for the positioning of the template in the copy window. In each case at the joint between two successive films there is an adhesive point, in which, for. B. the two film ends are connected by means of an adhesive tape 2. At the gluing point, the film is also provided on both sides with a crescent-shaped recess 1 b. The film glue points can be scanned by suitable sensors in the device. These can either be infrared light barriers that respond to the adhesive tape 2 or light barriers or mechanical sensors that detect the crescent-shaped cutouts 1 b on both sides.

• In der Meßstation 6 ist zusätzlich ein Fühler 45 für Klebestellen des Filmbandes vorgesehen. Ein Filmtransport 46 wird von einem Motor 51 angetrieben. Der Speicher 17 enthält eine obere Umlenkrolle 18, die unter Federspannung sich von oben nach unten und umgekehrt bewegen kann, um den zwischen den beiden Stationen befindlichen Film 1 gespannt zu halten. An der Halterung der Rolle 18 befindet sich ein Arm 18a, der in der in Fig. 3c gezeigten unteren Endstellung der Rolle 18 einen Mikroschalter 47 betätigt. Diese untere Endstellung der Rolle 18 markiert den minimalen Füllgrad des Speichers 17.

In order to reliably transmit the measured values from the measuring station 6 to the exposure control device in association with the copying templates, the following assemblies are also present in an embodiment of a copying machine according to the invention, which is shown schematically in FIG. 3:

• In the measuring station 6, a sensor 45 is additionally provided for adhesive spots on the film tape. A film transport 46 is driven by a motor 51. The memory 17 contains an upper deflection roller 18 which can move under spring tension from top to bottom and vice versa in order to keep the film 1 located between the two stations taut. On the holder of the roller 18 there is an arm 18a which actuates a microswitch 47 in the lower end position of the roller 18 shown in FIG. 3c. This lower end position of the roller 18 marks the minimum filling level of the store 17.

Furthermore, a sensor 48 for the gluing points (16) is provided in the copying station, and a film drive device 49 with a pair of rollers, which is driven by a motor 52. With one of the rollers a transport length measuring device, for. B. a slotted disc 50, the divisions can be scanned by a light barrier arrangement, not shown. This transport length measuring device gives pulses for each step covered, so that transport lengths can be measured by a number of steps given to a pulse counter.

The glue points on the film tape 1 are designated by the letter KI, the glue point still in front of the measuring station 6 being identified by the index x, ie by Kl _x . The next gluing point in the direction of flow has the designation Kl _x-1, further gluing points have the designations Kl _x - ₂ and Kl _x-3 - Based on this situation shown in Fig. 3a, a monitoring process is to be carried out which ensures that measured values from the measuring station 6 can also be safely assigned to the associated film strip in the copying station 19. For this purpose, a program is called, which runs in various steps from a computer, not shown, which are shown in FIGS. 3a-e. In phase 3b, the adhesive point Kl _{x has reached} the sensor 45 and leads to the stopping of the transport motor 51. The adhesive point Kl _x thus remains in the sensor 45. At the same time, the transport device 49 continues the film transport through the copying station, the copying process being expediently terminated immediately for initial runs in or after an error has occurred and the further film run takes place without copying. This phase with the film transport 46 stopped and the film transport continuing in the copying station is illustrated by the absence of an arrow at 46 and an arrow at 49.

Due to the continued film transport in the copying station, film is continuously removed from the memory 17, which leads to the minimum filling according to FIG. 3c being reached, as a result of which the microswitch 47 is actuated by the arm 18a. The actuation of the microswitch 47 has the consequence that a counter of the transport length measuring device 50 is set to zero and from now on measures the transport length. At the same time, the transport 46 is switched on again and the transport 49 continues. Since the speed of the transport 46 in the scanning station 6 is higher than that in the copying station, the memory 17 fills up again according to FIG. 3d. When the microswitch 47 is actuated, a monitoring window is activated on the counter contained in the transport length measuring device 50, which initially makes the glue point sensor 48 ineffective. The monitoring window has approximately the extent of an adhesive point and begins at a distance from the sensor 48 which corresponds to the distance (in terms of film length) between the sensor 48 and the sensor 45 with minimal memory filling according to FIG. 3c.

When the two film transport devices according to FIG. 3d are restarted, the microswitch 47 is opened again and the adhesive point Kl _x moves in the direction of the scanner 48. In between, however, there is the adhesive point KL _x-1, which has no effect due to the blocking of the sensor 48.

However, when the glue point Kl _{x reaches} the sensor 48, the transport length measuring device 50 has just activated the sensor 48 in the monitoring window, so that the signal from the sensor 48 is passed on. This already ensures that the adhesive point Kl _x is the one that was detected at the sensor 45 at the start of the monitoring process. This releases the transfer of the measured values for the originals lying behind the glue point Kl _x in the exposure control device, so that the correct measurement data for the originals lying behind the glue point Kl _x then starts again when the copying process begins again are available. This result is also not affected if Ki _j; at the sensor 48 further adhesive points Klx _{+ have passed} the sensor 45. The measured values determined for the subsequent master copies are stored and then passed on to the copying station in the order in which the adhesive points pass through the sensor 48.

If no adhesive point reaches sensor 48 within the monitoring window, a warning signal can be issued.

The process described is initially intended as initial monitoring when a new film is being fed in or in the event of discernible irregularities, e.g. B. after repairs or otherwise moving back the film in the film stage of the copying station. With a slight modification, this process can also be routinely carried out on a random basis, e.g. B. at every tenth glue point. Then, however, neither the copying process must be prevented nor the sensor 48 blocked. The monitoring window is then only effective to the extent that it is checked whether an adhesive point actually passes the sensor 48 in the monitoring area. If this is not the case, a warning signal can be sent to the operator to check the device.

The function of the synchronism monitoring according to the invention is independent of the type of adhesive point sensor used or the transport length measuring device 50. For example, instead of the slotted disc, the motor 52 could also be designed as a stepping motor, and the transport length measuring device is then simply designed as a pedometer.

Claims (7)

1. Process for monitoring the synchronism of the film advancement and the measured data in a roll copying apparatus having a measuring station (6), a copying station (19) and, situated between the latter, a store (17) of variable filling length, characterised in that in order to induce the reliable allocation of the measured data to the originals (1 a) the first film splice passing through the measuring station is detected and arrested with the aid of a first splice feeler (45), the filling length of the film store is reduced to a prescribed minimum value by transporting the film through the copying station, measurement of the transported film length is begun in the copying station and at the same time the film transport is continued in the measuring station with a speed corresponding at least to the speed of transport in the copying station, the film in the copying station is examined for the presence of the aforementioned first film splice by means of a second splice feeler (48) at a place in the film which, at the beginning of the measurement of the transported film length, was located in the film-measuring station at a film length distance from the second splice feeler (48) corresponding to the aforementioned minimum filling length.

2. Process according to Claim 1, characterised in that the place in the film is located in a film area which corresponds with a monitoring window and in particular has the length of a film splice.

3. Process according to Claim 1 or 2, characterised in that the sensing of splices in the copying station is blocked between the beginning of the measurement of the transported film length and the opening of the monitoring window and the film is transported without treatment through the copying station.

4. Process according to one of Claims 1 to 3, characterised in that if, at the end of the monitoring window, no splice signal of the feeler in the copying station has been received, the transport is stopped and a warning signal is delivered.

5. Process according to Claim 1, characterised in that the monitoring of the synchronism during the copying operation is repeated at random, while copying and the detection of splices by the feeler in the copying station are continued, and in that if no splices appear in the region of the monitoring window at the feeler of the copying station a warning signal is delivered.

6. Process for allocating measure data to the originals to be copied of a film strip comprising several films of varied length joined by splices, in the copying station of a roll copying apparatus having a measuring station, a copying station and, situated between the latter, a store of variable filling length, characterised in that in order to induce the allocation process the first film splice passing through the measuring station is detected and arrested with the aid of a splice feeler (45), the filling length of the film store is reduced to a prescribed minimum value by transporting the film through the copying station, then the film transport is continued in the measuring station with a speed corresponding at least to the speed of transport in the copying station and at the same time measurement of the transported film length is begun in the copying station and in that when the splice arrives in the copying station after having covered a film path length equal to that between the measuring station and the copying station for a minimum filling of the film store, the measured values for the original to be copied lying upstream of the splice are released to an exposure control device.

7. Photographic roll copying apparatus for carrying out the process according to one of Claims 1 to 4, having a guideway for the originals to be copied consisting of individual films spliced together to form long strips, having a measuring station arranged along this guideway for detecting the density values of a relatively large number of originals to be copied of a particular film and a feeler for splices between consecutive individual films, having a copying station for carrying out the copying process according to the measured density values and a second feeler for splices and having a film store arranged between the two stations, characterised in that the capacity of the store (17) of variable filling length is sufficient to receive at least half of the longest standard individual film, in that a film transporting device (46, 51), which can be stopped by the corresponding splice feeler (45) is provided in the measuring station (6), a further film transporting device (49, 52) with a device (50) for measuring the transported film length is provided in the copying station (19), in that a feeler (47) indicating the minimum filling length is arranged in the film store (17), which feeler (47), on being actuated, sets in operation the device (50) for measuring the transported film length and releases the film transporting device (46, 51) in the measuring station (6), and in that, upon the arrival of a splice Kl_x at the feeler (48) in the copying station (19) after a transported length corresponding to the film length between the two feelers (45, 48) for a minimum filling of the store, the device (50) for measuring the transported film length releases the transfer of the density values measured after this splice Klx to an exposure control device for controlling the exposure in the copying station (19) of the originals following this same splice KIX.

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